A compound, 15,19-Epoxy-3H-pyrido[2,1-c][1,4]oxaazacyclotricosine-1,7,20,21(4H,23H)-tetrone, 5,6,8,11,12,13,14,15,16,17,18,19,24,25,26,26a-hexadecahydro-5,19-dihydroxy-3-[(1E)-2-[(1R,3R,4R)-4-hydroxy-3-methoxycyclohexyl]-1-methyl ethenyl]-14,16-dimethoxy-4,10,12,18-tetramethyl-8-(2-propenyl)-, (3S,4R,5S,8R,9E,12S,14S,15R,16S,18R,19R,26aS), also known as FK506 as well as tacrolimus disclosed by EP 184162 and U.S. Pat. No. 4,894,366 is useful as an immunosuppressant. Another compound, 15,19-Epoxy-3H-pyrido[2,1-c][1,4]oxaazacyclotricosine-1,7,20,21(4H,23H)-tetrone, 8-ethyl-5,6,8,11,12,13,14,15,16,17,18,19,24,25,26,26a-hexadecahydro-5,19-dihydroxy-3-[(1E)-2-[(1R,3R,4R)-4-hydroxy-3-methoxycyclohexyl]-1-methylethenyl]-14,16-dimethoxy-4,10,12,18-tetramethyl-, (3S,4R,5S,8R,9E,12S,14S,15R,16S,18R,19R,26aS)-, also known as immunomycin as well as FK 520, disclosed in EPO Publication No. 0184162 is also useful as an immunosuppressant. Many other derivatives of these compounds as well as structural analogues have immunosuppressant property.
U.S. Pat. No. 5,508,398-discloses a process for separating a neutral non-polypeptide macrolide from acidic, basic and non-polar neutral impurities present in a concentrate of fermentation broth extracts or mother liquors containing said neutral macrolide which comprises in any order extraction step (a) and optionally one or both of steps (b) and (c), wherein (a) involves extraction with aqueous base, (b) involves extraction with aqueous acid and (c) involves treatment with non-aromatic hydrocarbon solvent.
U.S. Pat. No. 5,616,595 discloses a process for recovering water insoluble compounds (including FK506, FK520 and rapamycin) from a fermentation broth includes sequential steps of concentrating, solubilizing and diafiltering the compound of interest, all through a single closed recirculation system to recover the compound for further downstream purification.
Process for separation of tacrolimus from its related impurities is disclosed in U.S. Pat. No. 6,492,513. The process involves treatment of sulfonic acid group-containing ion exchange resin with silver ions. Alkenyl-side chain containing tacrolimus is separated from its alkyl-side chain containing analogs.
U.S. Pat. No. 6,576,135 discloses a process for similar separation. Tacrolimus along with the impurities is adsorbed to a nonionic adsorption resin followed by elution with an aqueous solvent containing silver ions.
Wang-Fan et. al. Reported a method for separation of tacrolimus from immunomycin using centrifugal counter-current chromatography. (Wang-Fan W., Kusters E., Lohse O., Mak C., Wang Y., Journal of Chromatography A, 864 (1999) 69-76).
The present invention is about a novel process for purification of macrolide compound. Here a easily scalable ammonia treatment is used to remove acidic impurities.